Field of the Invention
The present invention relates to a traveling stop control device for a transport vehicle and further, to a transport vehicle with the device.
Description of the Related Art
In open pit mines or the like, a transport vehicle such as a dump truck travels for transporting evacuated ore or earth and sand. The transport vehicle loads the transport object on its vessel (body) at a loading site and transports the loaded transport object to an earth dumping site to perform earth discharging. A bund for restraining the transport vehicle from traveling outside a traveling area is disposed at the earth dumping site. Further, also at an apron, a bund for a transport vehicle is provided for safety purpose. It is important to stop the transport vehicle safely when the same is brought into contact with the bund. The importance is high particularly in mine fields or the like in which unmanned transport vehicles travel.
A technology for stopping a vehicle at a bund is known from Japanese Patent Application Publication No. 2006-96191. This application describes the contents “A stop control module is connected to force detection sensors for detecting forces acting on four wheels in a front-rear direction, and when the variation in increase of the forces in the direction to effect a stop against the forces acting in the forward-rearward direction of the wheels on a moving-direction side exceeds a predetermined threshold value and when the magnitude in the direction to effect a stop of the forces acting in the forward-rearward direction of the wheels on the moving-direction side exceeds a predetermined value, it is judged that the wheels on the moving-direction side have come to collision with a bund member. Further, when the magnitude in the direction to effect a stop of the forces acting in the forward-rearward direction of the wheels on the moving-direction side exceeds a predetermined value and when the forces acting in the forward-rearward direction of the wheels on the moving-direction side and the forces acting in the forward-rearward direction of the wheels on the opposite side to the moving-direction side are opposite in direction, it is judged that the wheels on the moving-direction side are about to go over the bund member.” (refer to Abstract).
However, in the technology of the aforementioned Japanese Patent Application Publication No. 2006-96191, the contact of the vehicle with the bund is detected by a sensor that is used for contact judgment such as a force detection sensor, and thus, in the case of the force detection sensor falling in failure, there is a possibility that the contact with an obstacle cannot be detected correctly thereby making it unable to stop the vehicle.